Abstract

Acid mine drainage waters polluted by iron, several non-ferrous metals (mainly copper, zinc and cobalt) and sulphates as the main pollutants were efficiently treated by a lab-scale passive system consisting of an alkaline limestone drain and a permeable reactive multibarrier connected in a series. The multibarrier was filled by a mixture of solid biodegradable organic substrates (mainly of plant biomass) and was inhabited by different metabolically connected anaerobic microorganisms (mainly different heterotrophs including some iron-reducing and sulphate-reducing bacteria). The effluents from this system were rich in soluble organic compounds and were treated in a microbial fuel cell in which consortium of electrochemically active microorganisms used these compounds as donors of electrons for electricity generation.